Simple Electrical

Devices

1. Incandescent light

2. Switch

3. Circuit breaker

4. Flashlight

5. Power strip

6. Fuse

Incandescent Light

Light Bulb

Only about five parts. Name them.

Light bulb

Light under load

Current flow causes element to get hot and burn brightly.

Switch

Typical wall switch.

Switch On

Contacts are closed

Switch Off

Contacts are open.

SWITCH

How many parts?

Circuit Breaker

Circuit breakers are Safety Devices.

Circuit breaker

Notice the current rating.

Circuit breaker inside

Circuit Breaker Parts

1. On / Off Lever

2. Input terminal

3. Switch contact

4. Trip spring

5. Cocking arm

6. Bi-metallic strip

7. Output terminal

On Off

Closed Open

Tripped position

The cocking arm is not engaged with the bi-metallic strip.

Flashlight

Very simple circuit

All the required parts of a controllable circuit are

in the flashlight.

Flashlight control

Slide contact with the light bulb reflector ring.

Flashlight parts

Name the four parts of a controllable circuit in this

flashlight.

1. Voltage source 2. Conductive pathway

3. Load 4. Control

Power Strip

Power strip inside

Parts

1. Input cord

2. Circuit breaker

3. On / Off switch

4. Buss bars

Power strip inside

Three Buss Bars

The Fuse

Fuses are safety devices, like circuit breakers.

Fuses have a filament designed to burn and break the

circuit if too much current flows through it.

Do you see the filament? Fuses are also marked with the current

rating.

Some fuses are rebuildable, but most are one-time usage.

Automotive

Fuses

Industrial Fuses

Review

1. Name the parts of a light bulb.

Parts of a circuit breaker

Name the parts of a switch

Parts of a power strip

Parts of a flashlight